The Total solution for NCERT class 6-12
.Evaluate thedeterminants in Exercises 1 and 2.
(i) (ii)
Solution
(i) = (cos θ)(cos θ)− (−sin θ)(sin θ) = cos2 θ+ sin2 θ = 1
(ii)
= (x2 − x + 1)(x + 1) − (x −1)(x + 1)
= x3 − x2 + x + x2 − x + 1 − (x2 − 1)
= x3 + 1 − x2 + 1
= x3 − x2 + 2